Neurontin is an anticonvulsant medication indicated in the treatment of
epilepsy and neuropathic pain. Neurontin is known for having a relatively
mild side effect profile, and passes through the body unmetabolized.
Neurontin is similar in structure to the neurotransmitter GABA but is not
believed to act on the same brain receptors. Its exact mechanism of action
is unknown, but its therapeutic action on neuropathic pain is thought to involve
voltage gated calcium ion channels.
Neurontin has also been used in the treatment of bipolar disorder. However
the FDA has never approved Neurontin for the treatment of bipolar disorder,
and its use for this purpose is increasingly controversial. Some claim Neurontin
acts as a mood stabilizer and has the advantage of having fewer side effects
than more conventional bipolar drugs such as lithium and depakote. Some small,
non-controlled studies in the 1990s, most sponsored by Neurontin's manufactuer,
suggested that Neurontin treatment for bipolar disorder may be promising.
However, more recently, several larger, controlled, and double-blind studies
have found that Neurontin was no more effective than (and in one study, slightly
less effective than) placebo, and the manufacturer has even haulted its own
studies regarding gabapentin and bipolar disorder. Despite this scientific
evidence against the efficacy of Neurontin in the treatment of bipolar disorder,
many psychiatrists continue to prescribe Neurontin for this purpose.
Neurontin has also been used (also without FDA approval) in the treatment
of anxiety disorders such as social anxiety disorder and obsessive-compulsive
disorder, in treatment-resistant depression, and for insomnia. Neurontin may
be effective in reducing pain and spasticity in multiple sclerosis.
Gabapentin (medication name) is still under patent, and is manufactured by
Pfizer under the brand name Neurontin. Neurontin is one of Pfizer’s best selling
drugs, and was one of the 50 most prescribed drugs in the United States in
2003. However, in recent years Pfizer has come under heavy criticism for its
marketing of Neurontin, facing allegations that behind the scenes Pfizer marketed
the drug for at least a dozen supposed uses for which the drug had not been
FDA approved. By some estimates, so-called “off-label” prescriptions account
for roughly 90% of Neurontin sales. While off-label prescriptions are common
for a number of drugs and are perfectly legal (if not always appropriate),
marketing for off label uses of a drug is strictly illegal. In 2004, Pfizer
agreed to pay a $430 million settlement for the illegal marketing of Neurontin
for off-label purposes, and further legal action is pending.
Pfizer is developing a successor to Neurontin, called pregabalin, which Pfzier
hopes will be approved for use in epilepsy and neuropathic pain, as well as
some of Neurontin's off label uses, especially anxiety disorders.
From Wikipedia, medication
information resource.